Is the choice of a standard zeroth‐order hamiltonian in CASPT2 ansatz optimal in calculations of excitation energies in protonated and unprotonated schiff bases of retinal?
Sign Up to like & getrecommendations! Published in 2018 at "Journal of Computational Chemistry"
DOI: 10.1002/jcc.25217
Abstract: To account for systematic error of CASPT2 method empirical modification of the zeroth‐order Hamiltonian with Ionization Potential‐Electron Affinity (IPEA) shift was introduced. The optimized IPEA value (0.25 a.u.), called standard IPEA (S‐IPEA), was recommended but… read more here.
Keywords: schiff bases; ipea; order hamiltonian; geometry ... See more keywords
High-order Hamiltonian splitting for the Vlasov–Poisson equations
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DOI: 10.1007/s00211-016-0816-z
Abstract: We consider the Vlasov–Poisson equation in a Hamiltonian framework and derive new time splitting methods based on the decomposition of the Hamiltonian functional between the kinetic and electric energy. Assuming smoothness of the solutions, we… read more here.
Keywords: order; order hamiltonian; hamiltonian splitting; high order ... See more keywords
Higher Order Hamiltonian Systems with Generalized Legendre Transformation
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DOI: 10.3390/math6090163
Abstract: The aim of this paper is to report some recent results regarding second order Lagrangians corresponding to 2nd and 3rd order Euler–Lagrange forms. The associated 3rd order Hamiltonian systems are found. The generalized Legendre transformation… read more here.
Keywords: legendre transformation; order hamiltonian; transformation; generalized legendre ... See more keywords
Existence of solutions for first-order Hamiltonian random impulsive differential equations with Dirichlet boundary conditions
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DOI: 10.3934/dcdsb.2021236
Abstract: In this paper, we study the sufficient conditions for the existence of solutions of first-order Hamiltonian random impulsive differential equations under Dirichlet boundary value conditions. By using the variational method, we first obtain the corresponding… read more here.
Keywords: impulsive differential; first order; order hamiltonian; random impulsive ... See more keywords